When using image data obtained from an imaging device, such as X-ray, CT, MRT/MRI, for example, for navigation or a computer assisted surgery system, the image date can be provided as a video signal. It is of relevance to detect if there is a new image or not, so that the navigation system or the computer assisted surgery system on demand can use the new content of the new image.
U.S. Pat. Pub. No. 2011/0058026 describes a system and method for detecting a status of an image device. U.S. Pat. Pub. No. 2011/0058026 describes the determination of an intensity of a range of an image outside a mask so that presence of a new image is detected when the newly triggered x-ray device has illuminated the anatomy resulting in a sudden increase in intensity.